A power outage can be an inconvenience for many, however for people who depend on life-saving medical equipment, even small power outages can be life threatening. Thoughtfully sized battery backup systems can save lives and allow people live independently. Battery capacity isn’t the only consideration though. Understanding the features and options available (new page) is also important.
Watts tell us how much power a device uses in the moment. For example, a brighter light bulb uses more Watts than a dimmer one.
Watt hours (or watts per hour) tell us how much power is consumed over time. Battery system capacity is mostly measured in Watt hours. Calculating Watt hours is easy. Simply multiply the power of the device (Watts) by the hours used each day.
Well, that’s a bit tricky. You can:
Now you are getting into electricity 101! Amps refer to the flow of electricity through a wire. Volts refer to how fast the flow of electricity moves through the wire. If you know the values for both amps and volts, the formula for calculating Watts is easy: Amps x Volts = Watts
Finding accurate voltage information for your device might be a challenge. So when in doubt, use the strategies from the list above to find out how many watts your device uses or consult with a qualified electrician.
Add up the Watt hours (consumption) for each of your important devices. The result will be your power needs per day. You can use this number to shop for the correct size battery backup system.
My Devices | Power (Watts) | Time/Day | Consumption (Watts x Time) |
---|---|---|---|
Oxygen Concentrator | 300 watts | 8 hours | 2400 Wh |
Medical Refrigeration | 75 watts | 8 hours (33% duty cycle) | 600 Wh |
Infusion Pump | 60 watts | 40 minutes | 26 Wh |
Mobile Phone | - | - | 12 Wh* |
Total | 3,038 Wh |